The present invention is directed to semiconductor processes and devices.
Since the early days when Dr. Jack Kilby at Texas Instruments invented the integrated circuit, scientists and engineers have made numerous inventions and improvements on semiconductor devices and processes. The last five decades or so have seen a significant reduction in semiconductor sizes, which translates to ever increasing processing speed and decreasing power consumption. Furthermore, so far, the development of semiconductors has generally followed Moore's Law, which roughly states that the number of transistors in a dense integrated circuit doubles approximately every two years. Now, semiconductor processes are pushing toward below 20 nm, a situation in which some companies are now working on 14 nm processes. Just to provide a reference, a silicon atom is about 0.2 nm, which means the distance between two discrete components manufactured by a 20 nm process is just about a hundred silicon atoms.
Manufacturing semiconductor devices has thus become more and more challenging and is pushing toward the boundary of what is physically possible. Huali Microelectronic Corporation™ is one of the leading semiconductor fabrication companies that has focused on the research and development of semiconductor devices and processes.
One of the recent developments in semiconductor technologies has been utilization of silicon germanium (SiGe) in semiconductor manufacturing. For example, SiGe can be used for manufacturing of complementary metal-oxide-semiconductor (CMOS) with adjustable band gap. While conventional techniques exist for SiGe-based processes, these techniques are unfortunately inadequate for the reasons provided below. Therefore, improved methods and systems are desired.